反应详情

温度

60 °C

H2O2 (30% in H2O; 153 μL, 1.5 mmol) was added dropwise over 1-2 min to a stirred solution of 4-chloro-6,7-dimethoxyquinazoline 1j (112 mg, 0.5 mmol), concentrated H2SO4 (54 μL, 1.0 mmol), 3-iodooxetane (183 mg, 1.0 mmol) and iron(II) sulfate heptahydrate (42 mg, 0.15 mmol) in DMSO (5 mL) at 60 °C. After 1-2 min a further portion of iron(II) sulfate heptahydrate (42 mg, 0.15 mmol) was added and the mixture was stirred at 60 °C for 30 min. Further H2O2 (153 μL, 1.5 mmol) and iron(II) sulfate heptahydrate (42 mg, 0.15 mmol) was added, and the mixture was stirred at 60 °C for 30 min. After allowing to cool, the mixture was poured into a 0.2 M solution of NaOH saturated with solid NaCl (30 mL) and Et2O (50 mL). The aqueous and organic layers were partitioned and the aqueous layer was extracted with Et2O (2 x 25 mL). The combined organic extracts were washed with brine (1 x 30 mL), dried (MgSO4), filtered and the solvent removed under vacuum to leave a crude oil. The oil was purified by preparative thin-layer chromatography using MeOH / EtOAc (1:9) as eluent to give the desired product 2j (47 mg, 36%).